[U-Boot] PCIe switch questions

[U-Boot] PCIe switch questions

[dbrazeau]

Hi. I'm planning on using a IDT PCIe switch on our custom board with a
PPC_460 cpu.  I have searched the internet and haven't found much in the way
of references of using a IDT PCIe switch and a PPC with U-boot.  I was just
wondering if I should expect any issue with U-Boot/Linux communicating with
devices connected to the PCIe switch. 

Are there special U-boot configuration requirement when using a PCIe switch? 
I've looked online and in U-boot documentation and haven't seen a whole lot
of PCI configuration options except for the environment variable pcie_mode
and disabling the PCI bus altogether.  

I just wanted to get some input and thoughts on what I should expect once I
get the hardware.  Thanks.
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[U-Boot] PCIe switch questions

[Stefan Roese]

On Friday 14 August 2009 01:33:57 dbrazeau wrote:
> Hi. I'm planning on using a IDT PCIe switch on our custom board with a
> PPC_460 cpu.  I have searched the internet and haven't found much in the
> way of references of using a IDT PCIe switch and a PPC with U-boot.  I was
> just wondering if I should expect any issue with U-Boot/Linux communicating
> with devices connected to the PCIe switch.
>
> Are there special U-boot configuration requirement when using a PCIe
> switch? I've looked online and in U-boot documentation and haven't seen a
> whole lot of PCI configuration options except for the environment variable
> pcie_mode and disabling the PCI bus altogether.
>
> I just wanted to get some input and thoughts on what I should expect once I
> get the hardware.  Thanks.

I know of at least one project with an PPC4xx (405EX in this case) used with 
PCIe switches. IIRC, this is working fine in both U-Boot & Linux. So I 
wouldn't expect too many problems on 460EX. And if there should be some 
problem it should be possible to fix them.

Cheers,
Stefan

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[U-Boot] PCIe switch questions

[Matthias Fuchs]

Hi,

we are using U-Boot on PPC405 and PPC440EPx CPU in systems that have a lot
of PCIe switches and PCIe/PCI bridges. Even multiple cascaded switches and bridges :-)
U-Boot has no problems with these architecture.

But of course nobody really knows if there are issue that you might run into.

Matthias

On Friday 14 August 2009 01:33, dbrazeau wrote:
> 
> Hi. I'm planning on using a IDT PCIe switch on our custom board with a
> PPC_460 cpu.  I have searched the internet and haven't found much in the way
> of references of using a IDT PCIe switch and a PPC with U-boot.  I was just
> wondering if I should expect any issue with U-Boot/Linux communicating with
> devices connected to the PCIe switch. 
> 
> Are there special U-boot configuration requirement when using a PCIe switch? 
> I've looked online and in U-boot documentation and haven't seen a whole lot
> of PCI configuration options except for the environment variable pcie_mode
> and disabling the PCI bus altogether.  
> 
> I just wanted to get some input and thoughts on what I should expect once I
> get the hardware.  Thanks.